Energy-Efficient Solid Forward Extrusion through Hybridization Based on Process-Integrated Resistance Heating

Abstract:

In this paper a hybridized solid forward extrusion process is proposed that uses a process-integrated resistance heating for the energy-efficient heating of the workpiece material in order to avoid the occurrence of chevron cracks. As for the process-integration of the resistance heating two variations are regarded: the preheating of the wrought material prior to the forming process as well as a resistance heating concurrent with the extrusion process. Based on a three-shouldered solid forward extrusion of Cf53 with emerging chevron cracks the broad temperature interval for crack elimination is derived from experiments where the wrought material is preheated in a furnace. With this derived temperature a numerical approach for the dimensioning of a resistance heating of both prior to the forming process and during extrusion is shown. The approach is based on solving the Fourier heat transfer equation using both numerical algorithms in MATLAB and finite element method (FEM) in Deform-2D. In a final step the two scenarios heating prior to and during the extrusion process are evaluated in terms of their energy-efficiency using FEM.

• Periodical: Key Engineering Materials (Volumes 554-557)
• Pages: 620-629
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.554-557.620
• Online since: June 2013
• Authors: Michael Terhorst, Fritz Klocke, Stefan Niebes, Fabian Schongen, Patrick Mattfeld
• Keywords: Chevron Cracks, Energy Efficiency, Hybridization, Solid Forward Extrusion, Warm Forming

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